Refrigerating apparatus



Dec. 6, 1932. H. B. HULL ET AL 1,889,896

REFRIGERATING APPARATUS Filed Feb. 27, 1928 2 Sheets-Sheet 1 c7 ,3 BINVENTORS QM l- W} z y 7eZAUATTORNEYS.

Dec. 6, 1932. H. B. HULL ET AL 1,889,896

REFRIGERATING APPARATUS Filed Feb. 27, 1928 2 Sheets-Sheet 2 n L O Q C s I IO 40% J J J fl 66 INVENTQRS H m ATTORNEYS.

Patented Dec. 6, 1932 UNITED STATES HARRY B. HULL AND DONALD E. REEVES,

PATENT OFFICE OF DAYTON, OHIO, ASSIGNORS '10 FRIGID- AIRE CORPORATION, OF DAYTON, OHIO, A CORPORATION OF DELAWARE REFRIGERA'IING APPARATUS Application filed February 27, 1928. Serial No. 257,227.

This invention relates to refrigerating apparatus and articularly to an improved construction of refrigerating element and 1ts arrangement within a refrigerating cabinet.

One of the objects of the invention is to provide an improved refrigerating element particularly adapted for small cablnets, which will occupy a small amount of space.

Another object of the invention is to provide an improved refrigerating element of the dry expansion type which both freezes ice and cools a cabinet effectively.

Further objects and advantages .of the present invention will be apparent from the following description, reference beinghad to the accompanying drawings, wherein a preferred form of embodiment of the present invention is clearly shown.

In the drawings: 4

Fig. 1 is an elevation of a refrigerating cabinet showing a cooling unit constructed and arranged according to the present in vention;

- Fig. 2 is a front elevation on .an enlarged scale of the refrigerating element;

Fig. 3 is a top plan view of the element partly broken away;

Fig. 4 is a side elevation of the element partly broken away; and

Figs. 5 and 6 are front elevations of the separate coils of refrigerating element before assembly.

It has heretofore been regarded as necessary to have refrigerating elements so placed in refrigerating cabinets of the household type that air can freely circulate over the entire surface of the refrigerating element. To this end the element has been placed at a considerable distance from the walls of the cabinets and baflies or partitions have been provided to direct the circulating air over the elements, a considerable space naturally being required between the element and baffle. This has caused the amount of space devoted to the refrigerating element to be very large in proportion to the total volume of cabinet, and in the case of very small cabinets, such as those provided for apartment houses, the problem of space available for devoted to air circulation over it when placed in the cabinet.

Referring particularly to Fig. 1, 10 desi nates a refrigerating cabinet of any suitab e construction which has a door opening 11, a back wall 12, side walls 13, and a top wall 14. The side walls and top wall meet at corners, in one of which we place a refrigerating element 15 which may be supplied with liquid refrigerant by any suitable refrigerating apparatus not shown, and which may be for example of the type shown in the patent to Osborn, No. 1,556,708, October 13, 1925. The refrigerating element is disposed in the corner as close to the walls as construction and frosting conditions will permit. It is placed sufficiently close to thetop wall eifectively to' noticeably increasing the amount of heat leakage thru the walls at this point. We have also found that the cooling element may be' closer to the top wall than to the side walls since the heat leakage in the downward direction thru the top wall is relativelysmall.

The refrigerating element includes a freezing compartment 19, (Fig. 2) to be more fully describedherein and means projecting from the freeing compartment away from the walls into the cabinet for cooling the air in the cabinet and setting up circulation. As shown inFigs. 3, and 4 this means is preferably a number of L-shaped fins 20 projecting below and to one side of the freezing compartment. The air may circulate freely between the fins, which arein intimate contact with the refrigerant and are chilled by it.

Beneath the refrigerating element is placed a defrostin pan 21, slidably supported on one of the food storage shelves 22 which is provided with a depression 23 serving as a guide to insure the placing of the pan directly beneath the refrigerating element. hen the refrigerating apparatus is operating the pan serves as a convenient storage for articles to be kept very cold, such as ice cubes, and when the refrigerating element is being defrosted the pan serves to collect the water which drips from the element. Air chilled by the element sinks into the pan and over- "flows into the cabinet, likewise the air chilled by the fins flows downwardly either into or around the pan and sets-up the circulation of air which refrigerates the cabinet in the well known manner.

Figs. 2, 3 and 4 show in detail one form of construction of the refrigerating element. This preferably includes an inner coil of tubing which is of the form shown in'Fig. 5 and an outer coil of tubing 26 which is of the form shown in Fig. 6. The refrigerant coil or conduit 26 is open, that is, this coil'is not insulated from the freezing coil or conduit 25 and the freezing compartments or sleeves and 31. Within the coil 25 is placed a freezin compartment 30 to receive a freezing container 31a. It has been found that the majority of the heat conducted away from such freezing containers in apparatus of this sort when freezing ice cubes for ex-.

ample, is conducted through the bottom of the freezing container and freezing compartment to the refrigerant in the coil 25, and that water can be frozen more quickly by securing the freezing containers along the bottom to a refrigerant conduit than by attaching the conduit in any other manner.

Therefore the bottom of the freezing compartment 30 is soldered to each convolution on the bottom of the coil. On top of the coil 8 second compartment 31 is placed, whose bottom is soldered to each convolution. The compartments are adapted to receive freezing containers or ice trays 31a. The coil 25 and compartments 30 and 31 constitute the freezing compartment 19, referred to above. The coil 26 is placed around the coil 25 and the two compartments, and is connected in series with the coil 25 by a connection 32 (Fig. 3). The two coils thus in effect form a single continuous conduit. One of the L- shaped fins 20 is soldered to the bottom and one side of each convolution of the coil 26, the latter being preferably formed of flattened tubing to provide a. maximum amount of fiat surface to be soldered to the fins. The convolutions of the coil 26 are held in place by a number of braces 34, some of which are soldered to the fins and others to the convolutions as shown in Fig. 3. The braces are also provided with portions 3442 which are soldered to the coil 25, thus positioning the two coils with respect to each other.

At the ends of the compartment beyond the coils are secured a pair of brackets 36 and 37 having feet 38 by which the refrigerating ele ment is supported on the top-wall of the cabinet. The front bracket 36 is slightly shorter than the rear bracket 37 in order that the compartments 30 and 31 may slope slightly from front to the rear and prevent accidental sliding out of the ice trays 31a due to vibration or other causes. A cover or shield 40 is secured to the front of the compartments.

This may be coated with vitreous enamel ormay be made of polished non-corroding metal such as Monel, in order to enhance the appearance of the cooling unit. The shield is provided with openings 41 and 42 registering with the compartments 30 and 31 respective? ly to permit the insertion of the ice trays. The rear bracket 37 is provided with a pair of lugs 43 and 44 which receive screws for attachin the expansion valve which is provided or the purpose of controlling the sup ply of refrigerant to the refrigerating element. The particular construction of the valve forms no part of the present invention and may be for example as shown in the application of Harry B. Hull, Serial No. 183,480, filed April 13, 1927. A thermostat bulb 51 is secured to the back of the compart mentsby a clip 52 to control the refrigerating apparatus in response to the refrigerating demand.

It will be appreciated that a refrigerating element must be of a given cross section in order to receive ice trays of a size which is regardedas essential in present-day practice. The necessary heat exchange surface for cooling small cabinets may then be made on such a refri erating element within a length considerably less than the depth of the cabinet. The element is therefore placed toward the front of the cabinet and the space between theend of the cabinet and the rear wall is used for the expansion valve. Space at either end of the refrigerating element within its sides would ordinarily be inconvenient for the storage of food, because if this space he left at the front of the element it should be left vacant to permit the withdrawal of ice trays, and if left at the back of the element it would be very difficult of access. It will therefore be appreciated that the refrigerating element provided occupies the minimum space and leaves the maximum space in the cabinet for convenient food.

- employed in the construction'of this refrigerating element permits the maximum freezing effect to be distributed'thruout the element because both freezing compartments are connected alternately along the length of the coil 25. consequently the freezing effect of the coil is distributed equally between the two compartments. Moreover the coil is connected to the bottom of each compartment which is the most favorable position for freezing articles within the compartments.

The coil 25 is designed to furnish suflicient refrigeration to freeze water in both compartments, and thecoil 26 which surrounds the freezing compartments is intended primarily for cooling the circulating air. The device is preferably operated so that the entire coil 25 is flooded withliquid refrigerant. The coil 26 may or may notbe entirely flooded. That is. when the apparatus is first assembled the expansion valve is so adjusted that frost appears on the whole of the first coil 25 and the second coil 26 is frosted from its point of connection to the first coil 25 to some point intermediate its ends. The frost line or point where the frosting -on the coil stops indi cates how much of the conduit is flooded. By properly proportioning the parts, the system may be operated so thatthe coil 26 and fins 20 do not remain coated with frost during the entire operation. It will be understood that the apparatus is'periodically operated. During the operating periods frost may form on the entire evaporator. but due to the large surface of fins exposed to the circulating air the fins can ordinarily be-defrosted during the periods when the device is not circulating refrigerant. This leaves the fins bare for the subsequent operating period and enables the transfer of the maximum amount of heat. The inner coil 25 can be completely coated with frostand remain frosted during the nonoperating periods, and thus protect the ice within the compartment 19 from being melted bv the circulating air.

While the form. of embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. Refrigerating apparatus comprising in combination, a cabinet having 'walls enclosing a compartment to be cooled, a pair of the walls forming a corner, and a refrigerating elementdisposed'in the corner, the refrigeratingelement including means forming an enclosure for a freezing container out of contact with the walls but sufiiciently close to one of them to prevent free circulation of air between the walls and the enclosure, and L-shaped fins projecting from the bottom and one side of the enclosure for cooling air in the cabinet.

conduit, and an open refrigerant conduit surrounding the first mentioned conduit and both sleeves to chill air circulating over said element to prevent absorption of heat by said air from the sleeves.

3. A refrigerating element for refrigerating apparatus adapted to be placed in the path of circulating air forcooling the air and for freezing ice, comprising in combination -a refrigerant conduit, a pair of freezing sleeves disposed in vertical alignment, the outer side of the bottom of each sleeve being directly secured in intimate thermal contact with said conduit, and an open refrigerant conduit surrounding the first mentioned conduit and both sleeves, and connected in series with the first mentioned conduit to chill air circulating over said element to prevent absorption of heat by said air from the sleeves, and means for supplying refrigerant to the first mentioned conduit.

4. A refrigerating element for refrigerating apparatus adapted to be placed in the path of circulating air for coolingthe air and for freezing ice, comprising in combination a coil of refrigerant conduit, a pair of sleeves disposed in vertical alignment, the outer side of the bottom of each sleeve being directly secured in intimate thermal contact with said coil, and an open coil of refrigerant conduit surrounding the first mentioned coil and both sleeves to chill air circulating over said element to prevent absorption of heat by said air from thelsleeves.

5. A refrigerating element comprisin in combination, a horizontally disposed re igerant conduit, a pair of horizontally extending freezing sleeves disposed in vertical alignment, said refrigerant conduit entirely surrounding the lower one of said pair of sleeves, the outer side of the bottom wall of each sleeve being directly secured in intimate thermal contact with said refrigerant conduit,- and an open-horizontally dis osed refrigerant conduit surrounding the rst mentioned conduit and both sleeves to chill air circulating over said element to prevent absorption of heat by said air from the sleeves.

6. A refrigerating element comprisin in combination, a horizontally disposed re rig erant conduit, aepair of horizontally extending freezing sleeves disposed in vertical alignment, said refrigerant conduit entirely surrounding one of said sleeves, and being directly secured in intimate thermal contact with the outer side of the bottom wall of each sleeve, and an open horizontally dis- Essed refrigerant conduit surrounding the st mentioned conduit and both sleeves to chill air circulatin over said element to prevent absorption of heat by said air from the sleeves, and means for supplying refrigerant .to the first mentioned condluit.

In testimony whereof we hereto aflix our signatures.

" DONALD H. REEVES.

HARRY B. HULL. 

